Universal Behavior of anomalous cross sections at threshold

P A MACRI; R O BARRACHINA

Belfast

Conferencia; XXVI International Conference on the Physics of Electronic and Atomic Collisions; 2011

Since 60 years ago, the behavior of cross sections with low energy respect to thresholds is estimatedby the Wigner threshold law (WTL)[1]. Although collisions at these energy regimes show conspicuous effects like resonances which are known to degrade the scope of the WTL, up to now there is no theoretical estimation of its range of applicability or even less how these effects modify its behavior. The importance of revealing these matters of low energy scattering areincreasingly more pressing with the advance of modern atomic and molecular physics fields suchas Bose-Einstein condensation, atom interferometers and atomic clocks. Collisions at thresholdsare experimentally tested now at unprecedentedly low energies.